1. Field of the Invention
The present invention relates to connectors for joining the ends of successive lengths of pipe or conduit and/or connecting a pipe or conduit to a housing or other mounting surface wherein the connection will be exposed to axial transverse and bending vibrations. In particular, the present invention relates to connectors for joining pipes to one another or to other structures in exhaust systems for vehicles.
2. The Prior Art
It is well known that, in vehicle exhaust systems, particularly those for heavy duty vehicles, such as large trucks or earth moving equipment, the internal combustion (i.c.) engines produces significant amount of vibration in the exhaust system. Operation of the motors at continuous speeds for prolonged periods of time can, especially, produce what are known as harmonic vibrations which can cause significant deflections in extended lengths of exhaust pipe and at locations where such pipes are mounted to structures such as brackets, engine manifolds, and the like. Repeated deflections and vibration along the exhaust pipe system can, in turn, cause the structures to weaken with time and ultimately fail. Further, such harmonic vibrations can also be transmitted through the exhaust pipes to the mountings of the pipes, promoting the loosening of the mountings, which can result in the sudden displacement of one or more components of the exhaust system, with the potential for both personal injury and equipment damage.
In addition to the vibrations caused by the operation of the motor of the vehicle, an exhaust system is also subjected to various tension, compression and bending forces which also arise during the operation of the vehicle. While individual exhaust system components could be made stronger and more massive to resist failure by fatigue, such constructions would be undesirable due to weight considerations. Further, by making individual elements stiffer, the vibrations are merely transmitted throughout the exhaust system to the mountings or other components and are not reduced or eliminated. Accordingly, it is desirable to isolate the exhaust system, or at least components of the system, from such vibrations and forces.
It is known that if the pipes of an exhaust system are divided and separated by non-rigid connections, rather than being constructed as continuous extended lengths, the development of harmonic vibrations from the motor is precluded or reduced. Such non-rigid connections can be advantageously employed to absorb other tension, compression and bending forces, apart from and in addition to the motor vibration.
It is therefore desirable to provide a connector for joining a length of exhaust pipe, to another pipe or to a mounting, such as an engine manifold, which connector joins the components in a non-rigid fashion and is capable of absorbing tension, compression, and bending forces, as well as the vibrational forces, without transmitting them from one exhaust system component to another.
Typical prior art flexible connectors often require welds at both ends, in order to achieve a strong, substantially fluid-tight connection between the connector and the other exhaust system components to which they are attached. It would be desirable to avoid the use of welds whenever possible, as such welds take time to perform, adding to the installation time of the connector, and increasing the overall assembly time of the vehicle or apparatus to which they are being attached.
In addition, such welds are often difficult to place properly, often requiring additional complexity in the construction of the flexible connector, in order to provide working space for accomplishment of the weld. Still further, there is always the possibility of a small flaw in the weld, leading to possible leakage of harmful exhaust gases, and/or the introduction of a physical weakness in the structure of the flexible connector attachment, leading to the expenditure of additional time for double-checking the quality of each weld being performed.
In some instances, a weld is undesirable, and in order to provide for some form of sealing, gaskets must be positioned at the interface between the flexible connector and the exhaust manifold or other component to which the connector is being attached. Such gaskets which are usually made from mica coated stainless steel, for example, could begin to experience leakage shortly after installation, and, presuming an exhaust manifold pressure in the vicinity of 4.5 psig, could have a leakage rate of over 0.5 liters per minute.
It would be desirable to provide an alternative to welding for the manufacture and/or installation of flexible connector apparatus, which would be less expensive, require less intensive examination upon completion and/or have an enhanced degree of reliability and/or manufacturability than welding techniques.
It would be desirable to provide a flexible connector apparatus and a method and apparatus for the manufacture and installation of same, which would employ fewer welds.
It would also be desirable to provide a weldless connection between a flexible connector apparatus and a component, such as an exhaust manifold, which does not rely upon the use of gaskets, which may deteriorate with use, and which could experience leakage when in use.
These and other objects of the invention will become apparent in view of the present specification including claims, and drawings.
The present invention comprises, in part, a flexible connector apparatus for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine. The apparatus comprises a bellows member, having an axis, first and second ends, and at least two substantially uniform convolutions disposed substantially adjacent the first of the two ends; and a flange member, positioned in circumferentially surrounding relationship to the bellows member, axially between the at least two substantially uniform convolutions of the bellows member.
The flange member included at least one attachment element, operably associated with the flange member and configured for attachment of the flange member to one of the first and second components of the fluid conduit system.
The attachment element further is configured to capture one of the at least two substantially uniform convolutions axially between the flange member and the one of the first and second components of the fluid conduit system, for forming, upon completed attachment of the flange member to the one of the first and second components, a substantially fluid-tight weldless seal between one of the at least two substantially uniform convolutions of the bellows and the adjacent end of the bellows member, and the one of the first and second components.
The axially opposite end of the bellows member is operably configured for attachment at least indirectly to the other of the first and second components, for forming a substantially fluid-tight connection therewith, toward enabling the substantially fluid-tight transportation of fluid from the one of the first and second components, through the flexible connector apparatus, to the other of the first and second components.
The flexible connector apparatus further comprises, in one embodiment, a liner tube structure insertably received within the bellows member. The liner tube structure, in turn, may comprise a first liner tube member having a radially outwardly extending annular flange at one end thereof, the first liner tube member being insertably received in the first end of the bellows member, such that at least a portion of one of the at least two substantially uniform convolutions is positioned axially between the flange member and the radially outwardly extending annular flange member, such that upon capture of the convolution between the flange member and the one of the first and second components, the radially outwardly extending annular flange member is also captured thereby; and a second liner tube member, telescopically engaged with the first liner tube member and insertably received within the bellows member, at a position distal to the first end of the bellows member, being operably configured for attachment at least indirectly to the other of the first and second components, for forming a substantially fluid-tight connection therewith, toward enabling the substantially fluid-tight transportation of fluid from the one of the first and second components, through the flexible connector apparatus, to the other of the first and second components.
A first substantially resilient spacer member is radially disposed between the telescopically engaged first and second liner tube members. Axially spaced first and second stop members, may be operably associated with the first and second liner tube members, respectively, for axially engaging the first spacer member therebetween, and limiting extensive axial movement of the first and second liner tube members relative to one another.
An end cap member may be provided, circumferentially surrounding a portion of the second end of the bellows member and a portion of the second liner tube member distal to the first liner tube member.
A second end cap member may be provided, circumferentially surrounding a portion of the first end of the bellows member and a portion of the first liner tube member distal to the second liner tube member, a portion of the second end cap member in turn being circumferentially surrounded by the flange member.
In an alternative embodiment of the invention, the bellows member is fabricated from at least two telescopically engaged tubular members, so that at least an innermost one of the tubular members overlaps others of the tubular members and, at least at the end proximate the flange member, extends axially beyond at least one other of the tubular members.
An end cap member may be provided, circumferentially surrounding a portion of the member, a portion of the end cap member in turn being circumferentially surrounded by the flange member.
In another embodiment of the invention, the convolution which is disposed between the flange member and the proximate end of the member is formed from a layer of no more than two telescopically engaged tubular members.
The present invention also comprises a method for manufacturing a flexible connector apparatus, for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine, comprising the steps of:
forming a first tubular member, having two ends;
forming a flange member, having an aperture therethrough having an inside diameter which is substantially equal to but greater than an outside diameter of the first tubular member;
configuring at least one attachment element on the flange member to enable attachment of the flange member to one of the first and second components;
inserting the first tubular member into the aperture of the flange member, to a position proximate one of the two ends of the first tubular member;
forming a plurality of at least two annular substantially uniform convolutions in the first tubular member, each such convolution having an outside diameter greater than the outside diameter of the first tubular member,
subsequent to formation of the at least two substantially uniform convolutions, the flange member being positioned between and substantially abutted by two of the at least two substantially uniform convolutions.
In one embodiment of the method, the method further comprises the steps of:
inserting a liner structure into the first tubular member after formation of the at least two substantially uniform convolutions; and
mechanically connecting the liner structure to the first tubular member.
The step of inserting a liner structure further comprises the steps of:
forming an first liner tube member having a diameter which is less than the diameter of the first tubular member;
forming an second liner tube member having a diameter which is less than the diameter of the first tubular member and predominantly less than the diameter of the first liner tube member;
telescopically inserting the second liner tube member into the first liner tube member, so that a portion of the first liner tube member overlaps a portion of the second liner tube member.
The step of inserting a liner structure may further comprise the step of:
positioning at least a first substantially resilient spacer member radially between the first liner tube member and the second liner tube member.
The method may further comprise the step of:
preparing the end of the first tubular member, proximate the flange member, so that, upon attachment of the flexible connector apparatus to one of the first and second components, one of the convolutions becomes entrapped and compressed between the flange member and the one of the first and second components, to form a substantially fluid-tight seal therebetween, toward precluding escape of fluid therefrom.
Preferably, the step of inserting the first tubular member into the aperture of the flange member, to a position proximate one of the two ends of the first tubular member further comprises the step of:
inserting an end cap member over the first tubular member, a portion of the end cap member being radially enclosed by the first tubular member and the flange member.
Alternatively, the method may further comprises the steps of:
forming one or more second tubular members, having a diameter less than the diameter of the first tubular member; and
inserting the one or more second tubular members into the first tubular member, so that at least the first tubular member overlaps the one or more tubular members, and at least at the end proximate the flange member, extends axially beyond at least one of the one or more tubular members.
The step of forming a plurality of at least two substantially uniform convolutions further comprises the step of:
forming the convolution which is to be disposed between the flange member and the proximate end of the member from a layer of no more than two telescopically engaged tubular members.
In a further embodiment of the invention, the invention also comprises a vibration decoupling connector apparatus, for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine. A mounting member is provided, having an aperture therethrough for the passage of fluid, the aperture having an inside surface, the mounting member being configured for attachment to a structural member in a fluid transport system. A pipe member has at least a first end region and a second end region.
A resilient flexible sealing member substantially surrounds at least a portion of the pipe member, and has two ends, a first of the two ends being operably connected to the first end region of the pipe member, a second of the two ends being operably connected to the mounting member, at least a portion of the second of the two ends of the resilient flexible sealing member being received within the aperture in the mounting member. An annular vibration damping member is radially positioned between a portion of the second end region of the pipe member, and a portion of the second end of the resilient flexible sealing member.
Means axially position the annular vibration damping member, relative to the portion of the second end region of the pipe member, the portion of the second end of the resilient flexible sealing member and the aperture of the mounting member, so that the annular vibration damping member is operably and effectively positioned within the region formed by the aperture of the mounting member.
The second end region of the pipe member is disposed in vibration absorbing contact with the vibration damping member, for enabling restricted relative axial, lateral and angular movement between the pipe member and the mounting member, when the mounting member is affixed to a structural member in a fluid transport system.
The resilient flexible sealing member is preferably positioned substantially against the inside surface of the aperture.
The means for axially positioning the annular vibration damping member comprises a first flange member, extending radially outwardly from the second end region of the pipe member; and a second flange member, extending radially outwardly from the second end region of the pipe member. The first and second flange members are axially spaced from one another, with the annular vibration damping member being axially enclosed between the first and second flange members.
The means for axially positioning the annular vibration damping member alternatively comprises a first flange member, extending radially outwardly from the second end region of the pipe member. At least a portion of the first flange member is substantially enclosed within and engaged by portions of the annular vibration damping member.
The invention further comprises means for sealing the resilient sealing member to a structural member in a fluid transport system. The means for sealing the resilient sealing member to a structural member in a fluid transport system comprises a portion of the second end of the resilient flexible sealing member, extending axially beyond the mounting member, and operably configured to be positioned axially between the mounting member and a structural member in a fluid transport system, and further operably configured to substantially circumferentially surround a fluid transport aperture in a structural member in a fluid transport system, so that when the mounting member is affixed to a structural member, a substantially fluid-tight seal is established between the second end of the resilient flexible sealing member, and the structural member.
In a preferred embodiment of the invention, wherein the bellows member has at least two annular convolutions along its length, and the means for sealing the resilient sealing member to a structural member in a fluid transport system comprises one of the at least two annular convolutions being positioned axially beyond the mounting member, so that when the mounting member is affixed to a structural member of a fluid transport system, the one of the at least two convolutions becomes captured and crushed between the mounting member and the structural member.
The annular vibration damping member preferably comprises a compressed metal mesh ring. Alternatively, the annular vibration damping member comprises a compressed ceramic mesh ring.
The invention further comprises an annular substantially rigid guard member, operably connected to the first end region of the pipe member, and substantially surrounding the resilient flexible sealing member.
The invention also comprises a method for manufacturing a vibration decoupling connector apparatus, for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine, comprising the steps of:
configuring a mounting member, with an aperture therethrough for the passage of fluid, the aperture having an inside surface, for attachment to a structural member in a fluid transport system;
substantially surrounding at least a portion of a pipe member, having at least a first end region and a second end region, with a resilient flexible sealing member with two ends;
operably connecting a first of the two ends to the first end region of the pipe member;
operably connecting a second of the two ends to the mounting member, at least a portion of the second of the two ends of the resilient flexible sealing member being received within the aperture in the mounting member;
radially positioning an annular vibration damping member a portion of the second end region of the pipe member, and a portion of the second end of the resilient flexible sealing member;
axially positioning the annular vibration damping member, relative to the portion of the second end region of the pipe member, the portion of the second end of the resilient flexible sealing member and the inner surface of the aperture of the mounting member, so that the annular vibration damping member is substantially circumferentially surrounded by the inside surface of the aperture of the mounting member,
disposing the second end region of the pipe member in vibration absorbing contact with the vibration damping member, for enabling restricted relative axial, lateral and angular movement between the pipe member and the mounting member, when the mounting member is affixed to a structural member in a fluid transport system.
The method further comprises the step of positioning the resilient flexible sealing member substantially against the inside surface of the aperture.
The step of axially positioning the annular vibration damping member comprises the steps of:
extending a first flange member, radially outwardly from the second end region of the pipe member;
extending a second flange member, radially outwardly from the second end region of the pipe member,
axially spacing the first and second flange members from one another, with the annular vibration damping member being axially enclosed between the first and second flange members.
The step of axially positioning the annular vibration damping member alternatively comprises the steps of:
extending a first flange member, radially outwardly from the second end region of the pipe member,
substantially enclosing at least a portion of the first flange member within and engaging the portion of the first flange member by portions of the annular vibration damping member.
The method further comprises the step of:
sealing the resilient sealing member to a structural member in a fluid transport system. The step of sealing the resilient sealing member to a structural member in a fluid transport system comprises the step of:
axially extending a portion of the second end of the resilient flexible sealing member, beyond the mounting member, and operably configuring the portion of the second end of the resilient flexible sealing member to be positioned axially between the mounting member and a structural member in a fluid transport system, and further operably configuring the portion of the second end of the resilient flexible sealing member to substantially circumferentially surround a fluid transport aperture in a structural member in a fluid transport system, so that when the mounting member is affixed to a structural member, a substantially fluid-tight seal is established between the second end of the resilient flexible sealing member, and the structural member.
In the method according to this alternative embodiment of the invention, the resilient flexible sealing member comprises a bellows member having at least two annular convolutions along its length, and the step of sealing the resilient sealing member to a structural member in a fluid transport system comprises the step of:
axially positioning one of the at least two annular convolutions beyond the mounting member, so that when the mounting member is affixed to a structural member of a fluid transport system, the one of the at least two convolutions becomes captured and crushed between the mounting member and the structural member.
Preferably, in this method, the annular vibration damping member comprises a compressed metal mesh ring. Alternatively, the annular vibration damping member comprises a compressed ceramic mesh ring.
The method alternatively further comprises the step of:
operably connecting an annular substantially rigid guard member to the first end region of the pipe member, and substantially surrounding the resilient flexible sealing member with the annular substantially rigid guard member.
In a still further embodiment of the invention, a vibration decoupling connector apparatus, for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine, comprises a mounting member, having an aperture therethrough for the passage of fluid, the mounting member being configured for attachment to a structural member in a fluid transport system. A pipe member has at least a first end region and a second end region. A resilient flexible sealing member substantially surrounds at least a portion of the pipe member, and having two ends, a first of the two ends being operably connected to the first end region of the pipe member, a second of the two ends being operably connected to the mounting member. An annular vibration damping member is radially positioned between a portion of the second end region of the pipe member, and a portion of the mounting member. Means are provided for axially positioning the annular vibration damping member, relative to the portion of the second end region of the pipe member and the aperture of the mounting member, so that the annular vibration damping member is operably and effectively positioned within the region formed by the aperture of the mounting member. The second end region of the pipe member is disposed in vibration absorbing contact with the vibration damping member, for enabling restricted relative axial, lateral and angular movement between the pipe member and the mounting member, when the mounting member is affixed to a structural member in a fluid transport system.
In yet another embodiment of the invention, the second end of the resilient sealing member extends at least partially into the aperture of the mounting member.
A still further embodiment of the invention comprises a vibration decoupler apparatus, for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine.
A mounting member has an aperture therethrough for the passage of fluid, the aperture having an inside surface, the mounting member being configured for attachment to one of the first and second components. A pipe member has at least a first end region and a second end region. A resilient flexible sealing member substantially surrounds at least a portion of the pipe member, and has two ends, a first of the two ends being operably connected to the first end region of the pipe member. A second of the two ends is operably connected to the mounting member, at least a portion of the second of the two ends of the resilient flexible sealing member extending through the aperture in the mounting member, and having a convolution formed therein to provide a radially inwardly turned lip, for forming, in part, upon completed attachment of the mounting member to one of the first and second components, a substantially fluid-tight weldless seal between the mounting member and said one of the first and second components.
An annular vibration damping member is radially positioned between a portion of the second end region of the pipe member, and a portion of the second end of the resilient flexible sealing member.
The second end region of the pipe member is disposed in vibration absorbing contact with the vibration damping member, for enabling restricted relative axial, lateral and angular movement between the pipe member and the mounting member, when the mounting member is affixed to a structural member in a fluid transport system.
The radially inwardly turned lip extends radially inward to a position proximate a peripheral region of the second end of the pipe member, for substantially deflecting exhaust gases away from the annular vibration damping member.
At least one axial positioning member maintains the axial position of the annular vibration damping member, relative to the portion of the second end region of the pipe member, the portion of the second end of the resilient flexible sealing member and the aperture of the mounting member, so that the annular vibration damping member is operably and effectively positioned within the region formed by the aperture of the mounting member.
A portion of the resilient flexible sealing member is positioned substantially against the inside surface of the aperture. The at least one axial positioning member comprises a first flange member, extending radially outwardly from the second end region of the pipe member. The at least one axial positioning member may further comprise a second flange member, extending radially outwardly from the second end region of the pipe member, the first and second flange members being axially spaced from one another, with the annular vibration damping member being axially enclosed between the first and second flange members.
Preferably, the annular vibration damping member comprises a compressed metal mesh ring. Alternatively, the annular vibration damping member comprises a compressed ceramic mesh ring.
The vibration decoupler apparatus may further comprise an annular substantially rigid guard member, operably connected to the first end region of the pipe member, and substantially surrounding the resilient flexible sealing member.
In an alternative embodiment of the invention, the vibration decoupler apparatus, for connecting first and second components of a fluid conduit system, such as an exhaust system for an internal combustion engine, comprises a mounting member operably configured for connection to one of first and second components of a fluid conduit system. A pipe member having at least a first end region and a second end region, is at least indirectly connected to the mounting member at the first end region thereof.
A resilient flexible sealing member substantially surrounds at least a portion of the pipe member, and has two ends, a first of the two ends being operably connected to the first end region of the pipe member, a second of the two ends being configured to be operably, at least indirectly, connected to a second of said first and second components of said fluid conduit system. An annular vibration damping member may be radially positioned around a portion of the second end region of the pipe member, and radially positionable within a portion of said second of first and second components of a fluid conduit system.
At least one axial positioning member maintains the axial position of the annular vibration damping member, relative to the portion of the second end region of the pipe member.
The annular vibration damping member and the resilient flexible sealing member are axially separated from one another, upon connection to the second of the first and second components of a fluid conduit system.
The orientation of the annular vibration damping member and the resilient flexible sealing member enables restricted relative axial, lateral and angular movement between the pipe member and the second of the first and second components of a fluid conduit system, when the vibration decoupler apparatus is connected to the second of the first and second components of a fluid conduit system.
Preferably, the first end region of the pipe member is positioned in an upstream region, and the annular vibration absorbing damping member is positioned downstream in relation to the second end of the resilient flexible sealing member.
The vibration decoupler apparatus may further comprise a cap member, circumferentially surrounding a portion of the first end of the resilient flexible sealing member and extending axially along a portion of the resilient flexible sealing member, for providing protection therefor.
The resilient flexible sealing member preferably comprises a bellows, having at least two convolutions.
The annular vibration damping member preferably comprises a compressed metal mesh ring, or alternatively, a compressed ceramic mesh ring.
The vibration decoupler apparatus may further comprise an annular connector member, operably affixed to the second end of the resilient flexible sealing member and configured to be affixed to the second of the first and second components of a fluid conduit system, upon connection of the vibration decoupler apparatus to the second of the first and second components of the fluid conduit system.